Sheneela Naz

The effect of payload length on QoS in IEEE 802.11s Wireless Mesh Networks

In recent years Wireless Mesh Networks (WMN) have gained lot of attention from service providers and industry due to low cost and instant deployment at both access and distribution level. The IEEE 802.11s standard addresses the need for such networks. In multi-hop networks, throughput decreases exponentially with the increase in number of hops. Thus providing QoS in multi-hop networks becomes a delicate process. The use of larger payloads can significantly enhance throughput and channel utilization. However, using larger payloads has some coupled tradeoffs. The selection of optimal payload length varies with the type of the data in the frame and flow requirements. This paper describes these tradeoffs and presents the effect of payload length on various QoS measures like throughput, jitter, packet loss ratio and end-to-end delay for different type of traffic classes and access categories.

Multi-Attribute Caching: Towards efficient cache management in Content-Centric Networks

Content Centric Networking (CCN) has gained much attention of the research community in past few years. The default caching strategy of CCN is to store at each content-router along the downloading path. While this helps in increasing content availability and quality-of-experience (QoE) by reducing delay and reducing server load, the approach is not resource-efficient as it introduces high cache redundancy. Hence, there is a need to devise efficient caching mechanisms that allows maximum availability of content while consuming minimum possible resources. In this paper, we propose Multi-Attribute Caching Strategy (MAC) for CCN Networks that is based on using multiple parameters instead of a single attribute. These parameters include hop count or distance, node degree, content popularity and available storage space at the nodes. The scheme promises to overcome inefficient cache utilization by intelligently selecting caching locations along the content delivery paths. Simulation results indicate that MAC reduces the cache load at each node while increasing network cache hit rate.

A dynamic caching strategy for CCN-based MANETs

Abstract Mobile environments are known for frequent disconnections among different parts of the network. This characteristic may lead to unavailability of data in some parts of the network, as the data source is not accessible due to partitions. Content Centric Networks (CCN) use in-network caching; this inevitably improves performance in mobile networks by decreasing the impact of dynamic topology. At the same time, limited storage space available at mobile nodes further signifies the need for an optimized decision regarding (1) which content to cache and (2) where to cache. With this in mind, we propose a Caching Strategy in CCN-MANET (CSCM) that dynamically adapts its caching decisions for each content, and selects optimal nodes for relocation of cached contents in case the old cache node moves to a disconnected region. In this paper, CSCM is implemented as a generic framework to work with existing cache approaches for improving data availability, data access time, and for reducing traffic and bandwidth consumption. Extensive simulation results show that CSCM improves performance in terms of content retrieval time, network traffic, and content relocation compared to traditional approaches.

Performance Analysis of IPv6 QoS for Multimedia Applications Using Real Testbed

Abstract IPv6 is intended to provide better network QoS than IPv4, however, service providers still lacking confidence to claim this. The reason lies in less IPv6 QoS mechanisms, evaluation for several challenging scenarios, i.e. live streaming and video conferencing, etc. In this paper, to overcome this issue, we focus on evaluation of IPv6 QoS mechanism i.e. Traffic Class (TC) on real testbed. For Traffic Class (TC) evaluation, several scenarios are implemented with different DSCP values i.e Default PHB (Per hop behavior), Assured Forwarding (AF), Class Selector and Expedited Forwarding (EF). For evaluation, several test cases are devised with a combination of multiple DSCP values of the above four categories.

Automatic Translation of Heterogeneous Data Models

Schema translation is the process of transforming schemas in heterogeneous data models into a single target data model. Today there exist various data models to save useful data. The need of schema translation rises due to the existence of wide range of prominent, heterogeneous database applications. Due to the increasing requirement of interoperability of autonomous databases, multi database system which consists of homogenous or heterogeneous databases are required to work in a cooperative environment. In heterogeneous multi database system, the translation of one data model to another data model is critical. In this paper, we present a data model translation between heterogeneous models. Our approach translates the schema and data of one model to the target schema and data. We use the concept of metadictionary to achieve translation. We use XML as the standard to perform core translation. Our approach can adopt new upcoming models and can change them to old models easily.

A Framework for Real-Time Resource Allocation in IP Multimedia Subsystem Network

IMS (IP Multimedia Subsystem) is designed to provide multiple-services and can be accessed from any access network. With the advent of new multimedia services; user requirement also changed and required delay tolerant services from the service providers. The new multimedia services demands the restrictions on network parameters and this can be achieved by analyzing the traffic flow from the core as well as access network capabilities. As access and core IMS network are independent of each other and does not exchange user SLA with each other. In this paper we proposed framework based on Session border controller (SBC) that proactively monitored the traffic statistics as well as interact with access network operator for getting user’s SLA and reserve resources accordingly. We are also proposing alterations in SIP invite and re-invite message to incorporate requested information. These alterations will be useful in ensuring availability of user’s handset capabilities to IMS core network. Index Terms — quality of service, IP multimedia subsystem, SIP, RTCP, SBC

Multi-way Association Clustering Analysis on Adaptive Real-Time Multicast Data

Classification of real time multicast data using payload-based analysis is becoming increasingly difficult with many applications that a network supports. In this paper, we set our goal to identify the recurrent patterns and classification of transport layer data, as an effective measure of anomaly-based intrusion detection. These patterns are identified by using association rules techniques such as Apriori and clustering algorithms. A simulation experiment was configured to verify the efficacy of the algorithms. We are able to find an association between flow parameters for network traffic from the simulated data. This paper contributes a possible approach of analyzing behavior patterns for building a network traffic intrusion detection system and firewall at Transport layer, by using unsupervised association rule mining and clustering techniques.